Teardown
Remove the crank pulley. In an M5 leave the car in 5'th with the e-brake pulled. In an A4 you'll have to remove the torque converter shield and pry a screw driver in to prevent the motor from turning. For newer A4's without the shield, remove the starter and lock the flex plate this way.
Use a breaker bar to remove the crank bolt.
Remove the pulley using a harmonic ballancer pulley remover tool.
Remove both radiator hoses from the radiator and engine.
Use a fuel line disconnect tool to remove the fuel lines and EVAP line.
Remove the plug wires and ICM.
Remove the alternator.
Unbolt the EGR for clearance.
Unplug the wiring harness from the TB and fuel rail and move it away.
Remove the 4 10mm fuel rail bolts and remove the fuel rail.
Dissassembly
Remove the upper intake.
Gently remove the alternator braket from the coolant pump and lower intake. Be careful as those plastic tubes are fragile (but cheap to replace).
Remove the valve covers.
Remove the rocker arms, rocker arm pedastal and pushrods.
Remove the lower intake. (There are 2 bolts inside, Driver rear and pass front)
Remove the lifter valve guides.
Pull the lifters up.
Remove the front cover. 3 bolts come up through the oil pan. 1 water pump bolt has to be unscrewed as you pull the cover off. Uncrew, pull, unscrew, pull, unless you want to remove the waterpump pulley.
If you drained the fluid low enough nothing should leak out now.
Cam Swap
Remove the spark plugs.
Rotate the cam sprocket so both the balance shaft mark is in the down position and the cam/crank marks line up. (This is not critical it just makes life easier).
Remove the cam bolt and gently remove the cam/crank sprockets w/timing chain.
Pull off the balance shaft sprocket on the cam.
Remove the cam plate. (Be careful not to strip the screws!)
Insert the cam bolt back into the cam to help you grip the camshaft and GENTLY and carefully pull it out without dinging up any of the bearings. You must pull it out straight.
Transfer your stock cams key into the new camshaft.
Clean off your new camshaft very good and oil it up with engine oil.
Put your stock camshaft bolt into the new camshaft and gently insert it into the engine making sure you do not scratch the bearings.
Torque down the camshaft plate.
Put on the balance shaft sprocket and line it up with the balance shaft timing marks.
Miscellaneous pics
The install process
Inside the motor
Parts
Camshaft
The heads
Combustion chamber
Intake port
Exhaust port
Thrasher springs & retainers vs stock
Note: Hold the mouse over the images for a brief description.